Silencer for gas-engine valve mechanism



G. H. CHARNOCK S'ILENCBRFOR GAs ENGINE VALVE MECHANISM Filed Aug. 17. 1923 Patented July 8, 1924.

omre stares GEORGE HENRY CI-IABNOCK, OF BUFFALO, NEW YORK.

SILENCER FOR GAS-ENGINE VALVE MECHANISM.

Application filed August 17. 1923. Serial No. 657,971.

To all whom it may concern:

Be it known that I, GEORGE HENRY CHAR1 Noon, a citizen of the United States, residing at Buffalo, in the county of Erie and State of New York, have invented a new and. useful Improvement in Silencers. for Gas-Engine Valve Mechanism, of which the following is a specification. v

In the type of gas engine valve mechanism now in common use known as an overhead valve an undue amount of slack is liable to be present between the outer end ofthe valve stem and the rockerarm which actuates this stem, which slack in time is likely to produce objectionable noise.

It is the object of this invention to provide a silencer for use between the valve stem and rocker arm which will take up this slack and prevent any noise and which is so constructed that any binding or cramping action is avoided but instead the valve mechanism will be permitted to operate freely, easily and without undue friction or wear on the parts.

I "he-present invention is an improvement on the construction for whichI filed appli: cation'for Letters Patent, February 9,1923, Serial No. 618,145.

Inthe accompanying drawings: Figure 1 is a fragmentary" vertical-section .of an internal combustion engine having. itsvalve mechanism equipped with my invention. Figure 2 is a fragmentarytopplan view of the engine embodying my improvements. Figure 3 is a vertical section on an enlarged. scale taken on line 33," Fig. 2. Figure l is afragmentary vertical i sectionflon a reduced scale,'taken on line 4+4,- Fig. 3'. Figure 5' is a detachedpersepctive view of th si e e -Similar characters of reference indicate corresponding parts throughout the several views.

Inasmuch as this invention is applicable to gasengines of various constructions the showing in the drawings is to be regarded as merely one suitable installation of my invention. As shown, this engine comprises abody or frame 5 containing a cylinder 6 a-head7 at the top of thecylinder, and a piston 8 reciprocating in the cylinder and having its connecting rod 9 coupled. with the crank of the driving shaft.

With'each cylinder is-associated a "valve mechanism comprising a fuel inlet valve and an exhaust valve by means of which livegaseous fuel is admitted to the cylinder and the products of combustion are discharged therefrom, which valves are operated respectively by means comprising rock leverslO, 11. As the mechanism associated with the inlet and exhaust valves is identical in construction, the following description relating to the mechanism for operating the inlet valve 12 will serve to describe the mechanism for operating the exhaust valve.

The inlet valve 12 is adapted to move toward and from a valve seat 18 arranged around the inner end of the fuel inlet or passage 1 1 inthe head of the-body. On its upper side this valve is provided with a vertical valve stem 15 which extends'to the exterior of the body and is guided in a sleeve 16 mounted in the upper part of the head.

Each of the valves is yieldiii'gly held in its upper closed position by a collar 17 mounted on each valve stem and engaging its upper side with a shoulder formed by a washer 19 interlocking with a groove 20 in the valve stem, and a spring 21 surrounding the valve stem and engaging its lower end with the guide sleeve 16 and its upper end with the underside of said collar.

The inlet and exhaust rock levers are pivotally supported side byside on a shaft 22 mounted on the top of the head and the inlet valve rock lever has its rock arm 28 arranged over the upper end of the stem of the inlet valve while its tail 25 is provided with a downwardly opening socket 24: which re ceives thespherical upper end 26 of an upright push rod 27. In the lower part of the body is rotatably mounted the valve shaft 28 provided with a rotary cam 18 engaging the lower end of a vertical tappet 29. The

latter slides in aguide sleeve 30 on the body or frame and transmits lifting movement to the push rod through the medium of a ball 31 interposed between the ball sockets 32, 33, formed on the opposing ends of the tappet and push rod.

The. silencer embodying my invention is constructed as follows 3trepresents an inner cross piece of sheet metal or thelike provided centrally with an opening 35which receives the outer part of the valve stem and rests with its opposite endsontheouter side of the collar 17. An outer cross piece. of. sheetmetalor the like is arranged'above the inner cross piece and formed so that its central part 36 is deflected inwardly and its opposite ends 37 are deflected outwardly. The outer side of the inwardly deflected part of the outer cross piece engages with the inner side of the rocker arm and the inner side of this part of this cross piece is arranged close to the outer end of the valve stem in the closed position of the valve. The opposite ends of the outer cross piece are provided with openings 40. Upon the opposite ends of the outer cross piece are mounted two guide sleeves'5O which preferably project inwardly from the same'and are arranged parallel with and on opposite sides or the valve stem. Each of these guide sleeves may be secured to the outer cross piece in any suitable or approved manner and preferably by providing the same with inner and outer collars or flanges 51, 52 which engage with the inner and outer sides of the respective end of the outer cross piece. Arranged lengthwise on opposite sides of the valve stem are two guide rods ll which have their inner ends secured to opposite ends of the inner cross piece while their outer parts slide in the guide sleeves 50 of the outer cross piece. The latter is yieldingly held in its elevated pouitionso that the cross pieces are separated by helical springs 4L2 each of which surrounds one of the guide rods and sleeves and bears at its inner end against the inner cross piece, while its-outer end bears against the inner side of the inner collar 51 on the respective vguide sleeve. Complete separation of the outerv cross piece. from the guide rods is prevented, when the silencer is removed from the. valve mechanism by means of stops 43 arranged on the to be engaged by the outer side of the outer cross piece. .i v I In assembling this silencer with the valve mechanism, the same is so. adjusted that when the valve is. closed by. its spring 21 and the rocker arm is in its highest position,

the slightest possible clearance is present between the valve stem and the outer cross piece, the parts being held in this relative position by the springs 4E2, which are undertension. The strength of these springs 42 is, however, less thanithat ofqthe valve,

spring 21, so as to ensure closing of the valve whenever the lowpart of the cam is presented to the tappet.- ,7

Whenever the high part of the cam is presented to the tappet, the rocker arm is turned so that the same moves inwardly or downwardly. During thetirst part of this inward movement of the rocker arm, the outer cross piece is first depressed until it bears against the upper end of the valve stem during which time the tension on the springs 21 is slightly increased. After the outer cross piece bears against the valve outer ends ofthe guide rods and adapted,

stem, motion is transmitted positively from the rocker arm to the valve stem, whereby the valve is opened in oppositionto the spring 21. As the rocker arm moves outwardly, the valve stem moves in unison therewith until the valve has seated, then the rocker arm continues its outward movement independently of the valve to a minute extent, suflicient to ensure tight closing of the valve, during which time the outer cross piece is separated slightly farther from the inner cross piece under the action of the springs 42. These springs at all times cause the motion of the rocker arm to be transmitted to the valve stem gradually and without shock, noise or undue wear, thereby causing the valve mechanism to operate silently and without tapping, thus avoiding the annoyance usually experienced by the operation of valve mechanism as heretofore constructed.

By providing the outer cross piece with the guide sleeves for sliding on the guide rods or pins 41, an extended bearing surface is formed between these parts which permits the same to slide freely .on each other and thus avoids undue friction and wear and enables the valve to be operated readily and effectively In the absence of these sleeves, the pressure ofthe rocker arm is liable to tip the outer cross piece laterally infone direction or another and produce a cramping, binding and wearin actionbetween the outer cross. bar an the: guide rods. These guide sleeves. are preferabl made ofbrass and the rodot iron whic further prevents these parts: from sticking on each other and instead permits: them to slide freely one relativelyfto the other and thus ensure smooth oper ation of the valve mechanism 7 A V I clalm as my invention:

1 v A silencer for a gas enginevalve mechr an sm havmg a valve stem, a rocker arm for" opening the valve and a spring forcloslng the valve, comprising two cross pieces one of which is, adapted to operate on said spring and theiothe r adapted to operate onf said arm, a guide sleeve arranged on one of sald cross pieces, a gtndepinshdmg; in sa d sleeve and connected with the other cross piece, and a spring interposed between said cross pieces. a i

2. silencer foriagasengine valve mechanism having' a valve stem, a rocker arm for opening the valve and a spring for closing the valve, comprisingtwo, crosspieces one of which is adapted tooperateon said spring and the other adapted to operate on said arm, guide sleeves adapted to be arranged on opposite sides of the valve stem and secured to one offsaid cross pieces,

guide rods adapted to be arranged on oppo-' site sidesof said valvejstem; and sliding in said sleeves and connected wi-th the other cross piece, and springs surrounding said guide rods and interposed between said cross pieces.

3. A silencer for a gas engine valve mechanism having a valve stem, a rocker arm for opening the valve and a spring for closing the valve, comprising two cross pieces one of which is straight and adapted to operate on said spring, and the other provided with an inwardly deflected central part adapted to be engaged by said rocker arm and outwardly deflected ends, guide sleeves secured to the ends of one of said cross pieces, guide pins secured to the ends of the other cross piece and sliding in said sleeves, and springs surounding said guide rods and interposed between said cross pieces.

4. A silencer for a gas engine valve mechanism having a valve stem, a rocker arm for opening the valve and a spring for closing the valve, comprising two cross pieces, one of which is straight and adapted to operate on said spring, and the other provided with an inwardly deflected central part adapted to be engaged by said rocker arm and out-' wardly deflected ends, guide sleeves secured at their outer ends to the outwardly deflected ends of one of said cross pieces, guide rods sliding in said sleeves and secured at their inner ends to the ends of the other cross piece, and springs surrounding said rods and interposed between said cross pieces.

5. A silencer for a gas engine valve mechanism having a reciprocating valve stem, a rocker arm arranged across the outer end of said stem and a spring surrounding the stem, comprising inner and outer cross pieces, said inner cross piece being adapted to operate against said spring and provided with a central opening which is adapted to receive said stem, and said outer cross piece having a central inwardly deflected part which is adapted to be arranged between the outer end of said stem and inner side of said rocker arm and also having its ends deflected outwardly and provided with openings, guide sleeves arranged on opposite sides of said inwardly deflected part and each arranged in one of said end openings of the outer cross piece, and provided with inner and outer collars engaging with the inner and outer sides of the outer cross piece, guide rods secured to said inner cross piece and sliding in said guide sleeves and springs surrounding said guide rods and sleeves and each bearing at its opposite ends against the inner cross piece and the inner collar of one of said guide sleeves.

In testimony whereof I aflix my signature.

GEORGE HENRY CHARNOCK. 

